Dorsal Collapse in Killer Whales

For some time now there has been a controversy of whether SeaWorld mistreats their animals; specifically, the orcas. The orcas are the stars of SeaWorld, but both visitors and experts are concerned about their treatment. But the current focus of their problems is the collapsed dorsal fin on nearly all the captive killer whales. Is it natural? Let us "sea" what the experts have to say.

What Experts Say

Jennifer Kennedy, a marine life expert, explained that an orca's dorsal fin can rise up to at least six feet and they are not supported by bone, but by collagen, a fibrous connective tissue. Still, it stays upright due to the long distances traveled by orcas. Kennedy explained that the water pressure against the dorsal fin helps, "keep the tissues inside healthy and straight, and it encourages the dorsal fin to remain straight."1Dr. Astrid van Ginneken, a former whale trainer, studied wild orcas as a part of Orca Survey since 1987 and has been an active investigator for over twenty years. She stated that less than one percent of orcas in the wild have collapsed dorsal fins. She also explained the collagen factor, but added on that there were more factors than simply water pressure.2One reason was patterned swimming. When forced to swim in circles and rarely straight lines, makes it impossible for orcas' dorsal fins to remain upright. Because wild orcas movements are far more random than their captive counterparts, the water pressure cannot weigh more heavily on one side than another. Rest at the surface was another reason, gravity begins to take its toll on the dorsal fin and it begins to collapse. Warmer water temperatures and lack of hydration also affected the dorsal fin, usually by affecting the collagen in the fin and causing it to deteriorate. Even the National Marine Fisheries Service has reported that “the collapsed dorsal fins commonly seen in captive killer whales do not result from a pathogenic condition, but are instead thought to most likely originate from an irreversible structural change in the fin’s collagen over time.”3

Upright Dorsal Fin

Source

Abnormal Fins Are Not Collapsed

One will take into account, however, that some findings have stated to find wild orcas with twisted, gnarled, wavy, and even bent dorsal fins. However, looking at photos provided by GlobalAnimal, there is a difference in the way twisted and wavy fins look from the bent fins of captive killer whales. They also mention that the collapsed dorsal fins in wild orcas are usually from aggressive behavior in males that results in injured dorsal fins; causing most of the deformities mentioned above4. Eric Hoyt, the author of ORCA: The Whale Called Killer, commented that age was a factor in the wavy dorsal fins. The larger the orca, the larger the dorsal fin. Once it reaches a peak point, the fin begins to get a wavy shape simply from not being able to support the fin as well as it had before.

The Problem With SeaWorld

But where the real controversy is stirred up is when SeaWorld begins making bold claims and spits out twisted information. Dr. Ingrid Visser, a marine mammal scientist who spent time researching the reasons behind collapsed dorsal fins in wild orcas, had found that twenty-three percent of wild orcas found only near British Columbia had collapsed dorsal fins. SeaWorld is being accused now, of distorting the information provided by Dr. Ingrid Visser, allegedly using only half of the data to convince the public that collapsed dorsal fins are natural in killer whales. When in actuality, according to Dr. Jeffrey Ventre, a former SeaWorld trainer, less than one percent of wild orcas in totality have collapsed dorsal fins.5To make matters worse, SeaWorld does not just deny that it gives out false information, it promotes it publicly to visitors even with the evidence provided. SeaWorld then attempts to pass on the collapsed dorsal fin as a genetic issue rather than one caused by their captivity. Claiming even further that dorsal fins differ between whales because they are 'unique' like humans hair.6

Source

Possible Solution?

Instead of attempting to cover up the issue of collapsed dorsal fins, SeaWorld could have simply explained that, yes, it is from captivity. Because that much is true. With killer whales not being able to move as freely in the tanks, that is something perhaps that cannot be avoided once they have been born into or have remained in captivity for some years. They could have then argued that killer whales born in captivity cannot be released into the wild. Why? Because they are not trained to live in the wild, they cannot hunt, they have poor immune systems that will be nearly useless in open oceans, and they have no experience in dealing with the possible dangers of the open ocean. With those issues, they can keep firm that it is safer to keep the killer whales born into captivity, in captivity, without refuting the evidence from experts and making themselves look untrustworthy.

A route SeaWorld could take is to stop bringing in orcas from the wild unless they are injured and they plan to release them back into the wild after they have been treated or healed. They should not encourage and force their killer whales into mating, instead, allowing it to happen naturally. With that, they'd be able to keep the comments about abuse by breeding at bay.

Your Thoughts?

Taking this all into account, what do you think? Is it natural to orcas to have collapsed fins? Should SeaWorld be held accountable for collapsed dorsal fins? Give us your opinion in the comment section.